Over the past fortnight, militias allied to the new government have begun besieging the city from both east and west, backed with discreet help from British, French and American special forces.

Even the opening skirmishes have seen more than 30 killed and hundreds more wounded, and there may be months of heavy casualties ahead as the troops attempt to dislodge up to 6,000 well-dug in Isil fighters.

With the country's war-ravaged hospitals already over-stretched, there are fears that British and Italian military hospitals could easily be overwhelmed unless other European nations play their part.

Libyan fighters at the frontline in Abugrein

Only fighters whose injuries are deemed too serious to be treated in Libyan hospitals are considered for airlift abroad. But with Libyan hospitals already short of highly qualified surgeons and running low even on basic items like anaesthetics, the number of injured who fit that criteria could be large.

It is understood that it was chosen partly because it is a much shorter airlift than taking them to the UK itself. Both Britain and Italy, which is Libya's former colonial power, have offered troops for training Libyan forces.

An MoD spokesman said: "The UK is committed to working with international partners on how best to support the new Libyan Government of National Accord. “No decisions have been made and it is too early to say what this support will look like.”

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